Hydrogen Generation Catalyzed by Fluorinated Diglyoxime−Iron Complexes at Low Overpotentials

Fe^(II) complexes containing the fluorinated ligand 1,2-bis(perfluorophenyl)ethane-1,2-dionedioxime (dAr^FgH_2; H = dissociable proton) exhibit relatively positive Fe^(II/I) reduction potentials. The air-stable difluoroborated species [(dAr^FgBF_2)_2Fe(py)_2] (2) electrocatalyzes H_2 generation at −0.9 V vs SCE with i_(cat)/i_p ≈ 4, corresponding to a turnover frequency (TOF) of ~ 20 s^(–1) [Faradaic yield (FY) = 82 ± 13%]. The corresponding monofluoroborated, proton-bridged complex [(dArFg2H-BF2)Fe(py)2] (3) exhibits an improved TOF of ~ 200 s^(–1) (i_(cat)/i_p ≈ 8; FY = 68 ± 14%) at −0.8 V with an overpotential of 300 mV. Simulations of the electrocatalytic cyclic voltammograms of 2 suggest rate-limiting protonation of an Fe“0” intermediate (k_(RLS) ≈ 200 M^(–1) s^(–1)) that undergoes hydride protonation to form H_2. Complex 3 likely reacts via protonation of an Fe^I intermediate that subsequently forms H_2 via a bimetallic mechanism (k_(RLS) ≈ 2000 M^(–1) s^(–1)). 3 catalyzes production at relatively positive potentials compared with other iron complexes

A Search for Low-Amplitude Variability in Six Open Clusters Using the Robust Median Statistic

We used point-spread function fitting and a differential ensemble determined from a robust median statistic (RoMS) to examine stars in six open clusters in a search for δ Scuti variables. In the search for new variable stars among hundreds or thousands of stars, the RoMS is proved more effective for finding low-amplitude variables than the traditional error-curve approach. This high-precision differential approach was applied to the open clusters NGC 225, NGC 559, NGC 6811, NGC 6940, NGC 7142, and NGC 7160. Thirteen variables, 29 suspected variables, and 65 potential variables were found, and time-series data of the variables are presented. Among the 13 variables we found nine new δ Scuti variables

The 2HA line of Medicago truncatula has characteristics of an epigenetic mutant that is weakly ethylene insensitive

BACKGROUND The Medicago truncatula 2HA seed line is highly embryogenic while the parental line Jemalong rarely produces embryos. The 2HA line was developed from one of the rare Jemalong regenerates and this method for obtaining a highly regenerable genotype in M. truncatula is readily reproducible suggesting an epigenetic mechanism. Microarray transcriptomic analysis showed down regulation of an ETHYLENE INSENSITIVE 3-like gene in 2HA callus which provided an approach to investigating epigenetic regulation of genes related to ethylene signalling and the 2HA phenotype. Ethylene is involved in many developmental processes including somatic embryogenesis (SE) and is associated with stress responses. RESULTS Microarray transcriptomic analysis showed a significant number of up-regulated transcripts in 2HA tissue culture, including nodule and embryo specific genes and transposon-like genes, while only a few genes were down-regulated, including an EIN3-like gene we called MtEIL1. This reduced expression was associated with ethylene insensitivity of 2HA plants that was further investigated. The weak ethylene insensitivity affected root and nodule development. Sequencing of MtEIL1 found no difference between 2HA and wild-type plants. DNA methylation analysis of MtEIL1 revealed significant difference between 2HA and wild-type plants. Tiling arrays demonstrated an elevated level of miRNA in 2HA plants that hybridised to the antisense strand of the MtEIL1 gene. AFLP-like methylation profiling revealed more differences in DNA methylation between 2HA and wild-type. Segregation analysis demonstrated the recessive nature of the eil1 phenotype and the dominant nature of the SE trait. CONCLUSIONS We have demonstrated that EIL1 of Medicago truncatula (MtEIL1) is epigenetically silenced in the 2HA seed line. The possible cause is an elevated level of miRNA that targets its 3'UTR and is also associated with DNA methylation of MtEIL1. Down regulation of MtEIL1 makes it possible to form nodules in the presence of ethylene and affects root growth under normal conditions. Segregation analysis showed no association between MtEIL1 expression and SE in culture but the role and mechanism of ethylene signalling in the process of plant regeneration through SE requires further investigation. The work also suggests that epigenetic changes to a particular gene induced in culture can be fixed in regenerated plants.This work was funded by the Australian Research Council (CEO348212) through the ARC Centre of Excellence for Integrative Legume Research (CILR)

HIV-1 Evolutionary Patterns Associated with Metastatic Kaposi's Sarcoma during AIDS.

Kaposi's sarcoma (KS) in HIV-infected individuals can have a wide range of clinical outcomes, from indolent skin tumors to a life-threatening visceral cancer. KS tumors contain endothelial-related cells and inflammatory cells that may be HIV-infected. In this study we tested if HIV evolutionary patterns distinguish KS tumor relatedness and progression. Multisite autopsies from participants who died from HIV-AIDS with KS prior to the availability of antiretroviral therapy were identified at the AIDS and Cancer Specimen Resource (ACSR). Two patients (KS1 and KS2) died predominantly from non-KS-associated disease and KS3 died due to aggressive and metastatic KS within one month of diagnosis. Skin and visceral tumor and nontumor autopsy tissues were obtained (n = 12). Single genome sequencing was used to amplify HIV RNA and DNA, which was present in all tumors. Independent HIV tumor clades in phylogenies differentiated KS1 and KS2 from KS3, whose sequences were interrelated by both phylogeny and selection. HIV compartmentalization was confirmed in KS1 and KS2 tumors; however, in KS3, no compartmentalization was observed among sampled tissues. While the sample size is small, the HIV evolutionary patterns observed in all patients suggest an interplay between tumor cells and HIV-infected cells which provides a selective advantage and could promote KS progression

Fe_4 Cluster and a Buckled Macrocycle Complex from the Reduction of [(dmgBF_2)_(2)Fe(L)_2] (L = MeCN, ^(t)Bu^(i)NC)

We report the syntheses, X-ray structures, and reductive electrochemistry of the Fe^(II) complexes [(dmgBF_2)_(2)Fe(MeCN)_2] (1; dmg = dimethylglyoxime, MeCN = acetonitrile) and [(dmgBF_2)Fe(^(t)Bu^(i)NC)_2] (2; ^(t)Bu^(i)NC = tert-butylisocyanide). The reaction of 1 with Na/Hg amalgam led to isolation and the X-ray structure of [(dmgBF_2)_(2)Fe(glyIm)] (3; glyIm = glyimine), wherein the (dmgBF_2)_2 macrocyclic frame is bent to accommodate the binding of a bidentate apical ligand. We also report the X-ray structure of a rare mixed-valence Fe4 cluster with supporting dmg-type ligands. In the structure of [(dmg_(2)BF_2)_(3)Fe_3(1/2dmg)_(3)Fe(O)_6] (4), the (dmgBF_(2))_2 macrocycle has been cleaved, eliminating BF_2 groups. Density functional theory calculations and electron paramagnetic resonance data are in accordance with a central FeIII ion surrounded by three formally Fe^(II)dmg_(2)BF_2 units

Establishing Observational Baselines for Two δ Scuti Variables: V966 Herculis and V1438 Aquilae

We have examined the previously understudied δ Scuti stars V966 Herculis and V1438 Aquilae. We find that V966 Her is a stable pulsator with a refined period of 0.1330302 days with a full V amplitude of 0.096 mag. We also find that V966 Her has an average radial velocity of +7.8 km s-1, a full radial velocity amplitude of 7.6 km s-1, and a v sin i = 63.8 km s-1. For V1438 Aql we report a revised Hipparcos period of 0.1612751 days with a full amplitude of 0.056. The average radial velocity is found to be -43 km s-1, with full amplitude of 9.7 km s-1, and a v sin i = 76.7 km s-1. Due to some anomalies seen in V1438 Aql we feel that a much larger photometric and spectroscopic campaign is required to determine the true nature of this star

Determinants of clinician adoption of regenerative therapies in the UK and Canada: an ophthalmology perspective

The determinants of adoption of regenerative medicine therapies are currently poorly understood. This study aims to draw comparison between the UK and Canada in terms of factors likely to affect healthcare adoption of future regenerative therapies in ophthalmology. Conducting semi-structured interviews with senior ophthalmologists in the UK and Canada, their perceptions of factors either enabling or limiting adoption were recorded and analyzed. A number of key concepts were extracted from the interview data, perceived by stakeholders to contribute to adoption. The core factors developed in this work will be of use to those looking to understand the opportunities and risks involved in securing clinician adoption in both the UK and Canada

Blood pressure management in ischemic stroke patients undergoing mechanical thrombectomy

The relationship between presenting blood pressure in acute ischemic stroke patients and outcome is complex. Several studies have demonstrated a U-shaped curve with worse outcomes when blood pressure is high or low. The American Heart Association/American Stroke Association guidelines recommend values of blood pressure \u3c 185/110 mmHg in patients treated with intravenous t-PA and permissive hypertension up to 220/120 mmHg in those not treated with intravenous t-PA. The optimal blood pressure target is less clear in patients undergoing mechanical thrombectomy. Before thrombectomy, the guidelines recommend a blood pressure \u3c 185/110 mmHg though patients with even lower systolic blood pressures may have better outcomes. During and after thrombectomy, the guidelines recommend a blood pressure \u3c 180/105 mmHg. However, several studies have suggested that during thrombectomy the primary goal should be to prevent significant low blood pressure (e.g., target systolic blood pressure \u3e 140 mmHg or MAP \u3e 70 mmHg). After thrombectomy, the primary goal should be to prevent high blood pressure (e.g., target systolic blood pressure \u3c 160 mmHg or MAP \u3c 90 mmHg). To make more specific recommendations, large, randomized-control studies are needed that address factors such as the baseline blood pressure, timing and degree of revascularization, status of collaterals, and estimated risk of reperfusion injury

Settlement Rates and Settlement Stages in Compulsory Interest Arbitration

Dès qu'on traite de l'arbitrage obligatoire des différends, on se demande si cette procédure de règlement des conflits restreint la véritable négociation collective. La présente étude examine jusqu'à quel point des règlements sont atteints par la négociation et par les différentes étapes du processus de négociation en calculant les taux de ces règlements pour les différents stades ou étapes de négociation. Nous visons, entre autres, à établir jusqu'à quel point le comportement de règlement ou d'entente est différent selon que l'on soit dans un système d'arbitrage obligatoire ou de négociation avec droit de grève. Plus spécifiquement, nous cherchons à vérifier si les taux de règlement sont uniformément plus bas à tous les stades de règlement dans un système d'arbitrage obligatoire. Nous voulons aussi déterminer s'il y a des différences eu égard aux taux de règlement entre quatre systèmes d'arbitrage ontariens — la santé, les employés de la Couronne, les policiers et les pompiers. Enfin, nous comparons les taux de règlement dans le secteur de la santé, où il y a le plus grande nombre de règlements, avec les résultats d'une étude antérieure qui examine l'expérience initiale dans ce secteur suite à l'adoption de la loi sur l'arbitrage obligatoire. Notre étude est basée sur des données compilées par le ministère du Travail de l'Ontario, pour la période allant de 1982 à 1990, portant sur le règlement des conventions collectives. Ces données couvrent 28 043 règlements impliquant 3 557 613 employés dans trois systèmes différents de négociation. Le système « secteur privé avec droit de grève » (secteur privé), représente 55 % des règlements couvrant 43 % des employés. Le « secteur public avec droit de grève » (secteur public-grève), pour sa part, reflète un peu plus de 20 % des règlements pour 30 % des employés couverts. Finalement, un autre 20 % des règlements pour environ 25 % des employés couverts est associé avec le système « secteur public avec arbitrage » (arbitrage public).Nous distinguons cinq stades ou étapes de règlements : 1- la négociation directe, i.e. la capacité des parties de régler sans l'intervention d'un tiers ;2- faute de règlement, les parties ont recours à la conciliation ;3- un règlement final et volontaire est atteint après la conciliation ;4- l'arbitrage ;5- les arrêts de travail.Nous pouvons résumer les résultats de la façon suivante. D'abord, les tendances de règlements sous un système d'arbitrage diffèrent grandement de ceux atteints sous un système basé sur la grève. Dans le système « d'arbitrage public », la négociation directe n'a produit que 38 % des règlements.Par contre, le « secteur public-grève » a vu 59 % des règlements atteints par la négociation directe. Les règlements atteints durant les étapes intermédiaires de négociation comptent pour un peu moins de 25 % des règlements dans le système « secteur public-arbitrage ». Voici un contraste frappant avec le « secteur privé » où ces étapes de règlement ont eu des résultats positifs dans 44 % des cas. Cette proportion est de 38 % dans le secteur public-grève. Donc, le système d'« arbitrage public » produit moins de règlements volontaires. Le pourcentage de règlements atteints dans ce secteur sans recours aux procédures finales de solution des conflits est de 63 %, pourcentage beaucoup plus bas que les quelque 94 % dans le « secteur privé » et 96 % dans le « secteur public-grève ».Ensuite, il existe de grandes variations dans les taux de règlement entre les différents systèmes d'arbitrage. Même si les taux globaux de règlements ont été constamment plus bas en système d'arbitrage qu'en systèmes basés sur la grève, on a eu recours à l'arbitrage de façon beaucoup plus prononcée dans le secteur de la santé. En effet, la proportion des règlements conclus à l'étape de l'arbitrage dans ce secteur était du double de celle atteinte pour les policiers et pompiers et du tiers plus élevé que pour les employés de la Couronne. Ces résultats démontrent que les comportements de règlement varient considérablement selon les systèmes d'arbitrage. Ils suggèrent également que la véritable négociation collective est niée dans les systèmes d'arbitrage obligatoire. Alors que les taux de règlement étaient généralement plus bas dans les systèmes d'arbitrage par rapport à ceux basés sur la grève, le système d'arbitrage du secteur de la santé a produit le moins de règlements à l'occasion de la négociation directe et la plus haute dépendance à l'arbitrage. Les règlements volontaires étaient plus fréquents dans les petites unités de négociations. Cependant, la taille explique moins les comportements et règlements dans le secteur de la santé. La variation dans les taux de règlement entre les systèmes d'arbitrage dépend plus des différences dans les structures de négociation et autres particularités du processus de négociation que des différences dans les procédures d'arbitrage. Le volontarisme et l'indépendance étaient plus présents là où des pratiques de négociations étaient bien établies, l'arbitrage était prévisible et les conventions étaient de courte durée et de dates d'expiration communes. À l'opposé, les arrangements institutionnels dans le secteur de la santé (v.g. des pratiques de négociations plus complexes et diversifiées, moins de certitude eu égard aux résultats de l'arbitrage, des conventions plus longues et l'absence de date uniforme d'expiration) empêchent la négociation et accroissent la dépendance envers l'arbitrage.One of the prevailing concerns about compulsory interest arbitration is its possible effect on genuine collective bargaining. Numerous studies report overall settlement rates (i.e., the proportion of settlements achieved prior to the final impasse procedure) are lower in arbitration systems than in strike-based systems. This study attempts to provide a broader assessment of the effect of compulsory arbitration by calculating settlement rates for different settlement stages. Based on over 28,000 collective agreements negotiated in Ontario between 1982 and 1990, our results show that settlement rates were generally lower under arbitration. At the same time, settlement behaviour varied considerably across arbitration Systems. These differences are associated with specific institutional and organizational aspects in bargaining

Genomic regions linked to alcohol consumption in the Framingham Heart Study

BACKGROUND: Pedigree, demographic, square-root transformed maximum alcohol (SRMAXAPD) and maximum cigarette (MAXCPD) consumption, and genome-wide scan data from the Framingham Heart Study (FHS) were used to investigate genetic factors that may affect alcohol and cigarette consumption in this population-based sample. RESULTS: A significant sister:sister correlation greater than spouse correlation was observed for MAXCPD only. Single-point sib-pair regression analysis provided nominal evidence for linkage of loci to both SRMAXAPD and MAXCPD consumption traits, with more significant evidence of linkage to SRMAXAPD than to MAXCPD. One genomic region, chr9q21.11, exhibits significant multi-point sib-pair regression to SRMAXAPD. CONCLUSION: SRMAXAPD exhibits greater evidence for genetic linkage than does MAXCPD in the FHS sample. Four regions of the genome exhibiting nominal evidence for linkage to SRMAXAPD in the FHS sample correspond to regions of the genome previously identified as linked to alcoholism or related traits in the family data set ascertained on individuals affected with alcohol dependence known as COGA